Flexible shaft.



PATENTE MAR. 20

' C. F. G. MEHLIG.

FLEXIBLE SHAFT.-

yMILIGMION FILED 11.11222. 1905.

unirsi) STATES,

PATENT OFFICE.

CHARLES F. C.' MEHLIG, OF YORK, N. FLExlBLErs'HAFT.

Specification of LettersPatent.

Patented March 20, 1906.

Application filed May 22, 1905. Serial No. 261,488.

To a/ZZ whom t may concern,.- ,l

Be it known that I, CHARLEs F. C. MEHLIG, a citizen of the United States, residing in the borough of Manhattan, in the city, county,

and State of New York, have invented an Improvement in Flexible Shafts, of which the 'following is a specification.

My invention relates to a iiexible shaft adapted for transmitting movement and 'power from the driving-shaft of a xed or unitary prime mover to the driven shaft of some mechanical structure-or tool in line therewith or at any desired or necessary inclination or angle thereto. f

My' invention is applicable for general uses in-the arts and manufactures, and is espevcially adapted for use with dental engines and similar appliances or light machinery; and the object of my invention is to produce a iiexible shaft especially for such use and compact in form, but one in which there sha1 be substantially no lost motion or back- 'lash and a maximum amount of freedom of ymovement in any departure from a straight line and in any angle.

In carrying out my invention and in combination with the ends of the driving and driven shaft having sphere or socket terminations I employ spheres in pairs and sockets in pairs receiving the spheres, the spheres having axial pins and the sockets central opposite slots receiving the ends of the pins.

*The spheres are freev to move in the sockets' #guided by the ends of the axial pins, and the bearing of the pins in the slots of thesockets' provides for the transmission of Vmotion and power from the power-shaft to the driven shaft. The ends of the axial pins are prefer-l ably reduced and provided with flat opposite faces adapted to bear against the opposite faces of the slots. I have shown and prefer to place the axial pins of adjacent spheres at right angles to one another,` so as to percepti- Vbly increase the flexibilty of the connected parts forming the shaft. The pairs of sockets may be formed from a solid block of metal A or from a tube, and the sockets comprise about two hundred and fifty degreesof the cirle in order to engage the spheres effect- 1ve v Irlrthe drawings, Figures 1 and 2 are elevations and partial sections representing forms of my invention, the same being broken through to indicate indefinite length. Fig. 3 isan elevation of a pair of spheres; Fig. 4, a perspective view of one of the axial pins, and

the parts a a and b b I employ spheres in pairs and sockets in pairs, c c representing the spheres of each pair and d d the sockets of each pair, the sockets receiving the spheres and comprising aboutl two hundred and fifty degrees of the circle in order to engage the `spheres effectively. Each sphere is made with/a central aperture 2, each sphere receiving an axial pin having a body portion e, with reduced ends e', the pins fitting the holes 2 in the spheres and being free to turn therein.

The sockets centrally and oppositely are provided with slots 3 from the edgey inward,

Vthe slots receiving the ends of the pins. These @ends e are not only reduced kbut provided Awith flat opposite faces, the flat faces constituting substantially the reduction, as the ends of the pins lengthwise are thefull width of the pins, so that the opposite at'faces of the pins are adapted to bear against the opposite faces of the slots.. This provides a lib'- eral bearing-surface and reduces the wear incident to movement to a minimum, at the same time preventing thev pins turning and compelling the spheres to turnon the pins.

I have shown and prefer'to place the axial` pins of adjacent spheres at right angles to one another. These I have shown in both Figs. l and 2 of the drawings, the object thereof being to perceptibly increase the fiexibility of the connected parts forming the flexible shaft, it being! a fact that a greater flexibility is obtained by placing adjacent pins at right angles to one another or, in other words, alternate pins in like positions, than could possibly be obtained-by placing all lthe pins in like positions. The spheres c c are free to move in the sockets d d and they are guided at the ends of the axial pins in the .slots of the socket, and the bearing of the pins in the slots of the sockets provides for the transmission of rotary movement from one shaft to the other and the power of the power-shaft toy the drivenshaft, compelling the spheres to turn on the axial pins..

IOO

IIO

. In Fig. 1 I have shown the pairs of sockets y l formed from a s olid block of metal turned to external shape and bored out to receive the spheres, and after the spheres are put in place the edges of the sockets are turned in upon the spheres to hold the spheres in place.

In Fig. 2 I have shown the pairs of sockets as formed from a tube of metal, the central portion thereof being rolled in, and after the spheres are put in place the edges of the socketsA are turned in upon the spheres to hold the same in position.

The construction shown and described herein for my flexible shaft admits of the same being made of any size, according to the use to which the shaft is to be put, as it is adapted in large sizes for heavy work, as well as in small and light sizes for dental engines and similar light machines.

I claim as my inventionl. A flexible shaft, consisting of spheres in integral pairs and sockets in integral airs, the sockets receiving the spheres, axia pins passing through the spheres and engaging the sockets, and shaft-end terminations also connected with the said spheres and sockets.

2. A flexible shaft, consisting of spheres in integral pairs and sockets in integral airs, the sockets receiving the spheres, axia pins passing through the spheres and having reduced ends with llat opposite faces, the sockets having slots receiving the reduced ends of the axial pins, and shaft-end terminations connected respectively to the spheres and sockets.

3. A exible shaft, consisting of connected spheres in integral pairs and connected sockets in integral pairs, the sockets receiving the spheres and comprising about two hundred and fifty degrees of the circle in order to effectively engage the spheres, said sockets in pairs being. circumferentially and centrally reduced and having slots at opposite sides from their edges inward, axial pins passing through the spheres and having reduced ends received in the slots of the sockets, and shaftend terminations connected with the spheres and sockets.

4. A flexible shaft, consisting of connected spheres in pairs and connected sockets in pairs, the sockets receiving the spheres and comprising about two hundred and fifty degrees or the circle in order to effectively engage the spheres, said sockets in pairs bein@ circunfelentially and centrally reduced and having slots at opposite sides from their edges inward, axial pins passing through the s )heres and having reduced ends with lattene faces, said reduced ends being received in the slots of the sockets with their flat faces bearing against the edges of the slots, and shaft-end terminations connecting with the sockets and spheres.

5. A flexible shaft, consisting of connected spheres in pairs and connected sockets in pairs, the sockets receiving the spheres and comprising about two hundred and fifty degrees of the circle in order to effectively engage the spheres, said sockets in pairs being circumferentially and centrally reduced and havin@ slots at opposite sides from their edges inwar axial pins passing through the spheres the pins through adjacent spheres being at right angles to one another, the planes of the slots of the sockets being also at right angles to one another in each pair of sockets, the axial pins having reduced ends passing into the slots of the sockets, and shaft-end terminations connecting with the spheres and sockets.

6. A flexible shaft, consisting of connected spheres in pairs and connected sockets in pairs, the sockets receiving the spheres and comprising about two hundred and fifty degrees of the circle in order to effectively engage the spheres, said sockets in pairs being circumferentially and centrally reduced and having slots at o posite sides from their edges inward, axia pins passing through the spheres the pins through adjacent spheres being at right angles to one another, the planes of the slots ofthe sockets being also at right angles to one another in each pair of sockets, the axial pins having reduced ends passing into the slots of the sockets, said reduced ends having fiat opposite faces bearin(T against the edges of the slots, and shaft-end terminations connecting with the spheres and sockets.

Signed by me this 19th day of May, 1905.

C. F. C. MEHLIG.

`Witnesses:

GEO. T. PINCKNEY, S. T. HAviLAND. 

